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Tropical Storm Dorian appears to pose an increasing threat to the Southeastern United States, potentially including significant landmarks such as Disney World and the Kennedy Space Center.

As of Wednesday morning, Dorian was nearing hurricane strength, with sustained winds of 70mph. The storm's center should pass just to the east of Puerto Rico today and then have as much as four days to strengthen over open ocean before approaching the Florida coast.

Further Reading

The National Hurricane Center has ratcheted up its intensity forecast for Dorian, such that it is now predicted to come ashore as a Category 3 hurricane on Monday morning, near Kennedy Space Center on Florida's Atlantic coast.

The intensity forecast has really ramped up for a couple of reasons. First of all, the storm is no longer expected to interact with the mountainous terrain of Hispaniola. Its movement is also slower, meaning it will have several days over the very warm waters near the Bahamas, with moderate wind shear. Finally, the upper-atmosphere pattern is very favorable to intensification.

Enlarge/ The GFS forecast model ensemble predictions for Dorian show a range of possibilities for the track into Florida, and beyond.

Weathernerds.org

In terms of forecast track, there are some questions about the overall flow pattern in the upper atmosphere, so the landfall location carries more uncertainty than usual. A final landfall remains possible from north of Miami to Jacksonville. There are also questions about where the hurricane moves after it crosses the Florida peninsula. Dorian now seems more likely than not to reemerge in the Eastern Gulf of Mexico and eventually turn north, perhaps making a second landfall anywhere from the Florida Panhandle to Southeastern Louisiana.

Effects

The immediate concern is heavy rainfall over Puerto Rico and the US Virgin Islands, which could lead to flash flooding. Longer-term, the Florida coast faces the potential for storm surge and strong winds. Both of these will depend heavily on the intensity that Dorian reaches, and where the storm makes landfall, as effects are more significant to the right of the center.

As it now appears that Dorian will make a landfall at nearly a 90-degree angle to the Florida coast, storm surge effects will be amplified as the counter-clockwise motion of the storm's winds push water directly onshore.

Enlarge/ Very early precipitation accumulation forecast for the next seven days.

Pivotal Weather

In terms of winds, for now, Dorian is a relatively compact storm, so its worst winds may remain confined to within 50 or 75 miles (80-120km) of its center. Wherever the center crosses the Florida peninsula, it will have the potential to cause significant damage.

A final concern is heavy rainfall. The steering currents by this weekend, and into early next week, are not overly pronounced. A slower-moving storm means that some areas of the Southeastern United States—Florida, Georgia, Alabama, or the Carolinas—would see a large amount of precipitation and flooding. It is impossible to say at this time where the worst of this inland flooding will occur, but it likely will be somewhere to the right side of the storm's track, although not necessarily particularly close to the center.

In related news, he and his crew pulled out over one hundred million dollars from FEMA to fund his border ...things. Any underesourced response from the Feds is directly, 100%, on him.

Really don't want to see anyone get hurt...but it would be rather interesting to see the response (from people and administration) if a major storm hits and the relief response falls on its face unable to do anything for lack of funding.

Trump needs to win Florida in order to stay president, plus his gawd-awful pimp palace is there. There will be plenty of funding for Florida. Puerto Rico on the other hand, is apparently not part of the US, and if it were it wouldn't vote for Trump, so they will get nothing except cases of generic paper towels and bottled water left somewhere inaccessible to the general public...

But didn't Trump once say that the president of Puerto Rico was doing a fine job, or was that the president of Guam?

I think he said something about meeting with the president of Puerto Rico (apparently unaware that implies he met himself?) EDIT: Or maybe he said "President of Virgin Islands" either way it was nonsensical.

Maybe it was another Ars author, but I believe it was Eric who once said he was considering an article about all the variables and complexities involved in weather prediction that make it necessary to use supercomputers to develop prediction models. I'd still love to read that article. I'd also like to know about the tech and the specs of these prediction supercomputers.

IIRC, there was another Ars article on weather that recently said modern forecasts are limited to ten days for decent accuracy, due to chaos theory. Would be interesting to see how that factors into hurricane forecasting.

Maybe it was another Ars author, but I believe it was Eric who once said he was considering an article about all the variables and complexities involved in weather prediction that make it necessary to use supercomputers to develop prediction models. I'd still love to read that article. I'd also like to know about the tech and the specs of these prediction supercomputers.

The European Centre for Medium-Range Weather Forecasts (ECMWF), which is generally considered to be the most accurate forecaster, has a nice writeup of their computing resources here.

No worries. The VAB isn't going anywhere. And I think all the launch facilities are designed for this crap. Though repairs to the modified launcher for SLS will probably "need" another billion or so dollars after the storm.

I really wish intensity forecasting was a little more certain. As of yesterday the expectation was a tropical storm all the way to landfall. And today it's a major hurricane. That's the difference of not bothering to pull out the shutters vs. locking down everything and leaving. If the storm is just a big dump of water then we should be mostly fine. Florida is perhaps unique in its completely flat geography and all the smaller waterways, etc. We can take a lot more rain than most places without suffering city-erasing flooding. That and the fact that the Florida Water Management District is one of the most powerful political entities in the state. Nothing gets developed without being included in the water runoff management master plan. If nothing else, Floridians have gotten a lot of practice since Andrew after a long lull post-David.

The projected intensity was probably pretty accurate until the storm changed path. Previous predicted paths took Dorian over the Bahamas, which does a lot more to reduce hurricane intensity than you'd think for a bunch of tiny islands. Now the predicted path has Dorian curving around the Bahamas instead of directly over them.

Source: am a Floridian that has seen many bigger hurricanes diminish over the Bahamas.

I really wish intensity forecasting was a little more certain. As of yesterday the expectation was a tropical storm all the way to landfall. And today it's a major hurricane. That's the difference of not bothering to pull out the shutters vs. locking down everything and leaving. If the storm is just a big dump of water then we should be mostly fine. Florida is perhaps unique in its completely flat geography and all the smaller waterways, etc. We can take a lot more rain than most places without suffering city-erasing flooding. That and the fact that the Florida Water Management District is one of the most powerful political entities in the state. Nothing gets developed without being included in the water runoff management master plan. If nothing else, Floridians have gotten a lot of practice since Andrew after a long lull post-David.

The projected intensity was probably pretty accurate until the storm changed path. Previous predicted paths took Dorian over the Bahamas, which does a lot more to reduce hurricane intensity than you'd think for a bunch of tiny islands. Now the predicted path has Dorian curving around the Bahamas instead of directly over them.

Source: am a Floridian that has seen many bigger hurricanes diminish over the Bahamas.

I suspect you're right in that it's a track issue. But it probably has more to do with not going over Puerto Rico or Hispanola. Both islands' mountains weaken the hell out of storms. See also: Hurricane David.

In related news, he and his crew pulled out over one hundred million dollars from FEMA to fund his border ...things. Any underesourced response from the Feds is directly, 100%, on him.

Really don't want to see anyone get hurt...but it would be rather interesting to see the response (from people and administration) if a major storm hits and the relief response falls on its face unable to do anything for lack of funding.

Trump needs to win Florida in order to stay president, plus his gawd-awful pimp palace is there. There will be plenty of funding for Florida. Puerto Rico on the other hand, is apparently not part of the US, and if it were it wouldn't vote for Trump, so they will get nothing except cases of generic paper towels and bottled water left somewhere inaccessible to the general public...

But didn't Trump once say that the president of Puerto Rico was doing a fine job, or was that the president of Guam?

SpaceX better tie down the Starship prototypes, or hurry them into the new hanger.

The tall "megachurch" hangar is almost complete. From the most recent photos, they are installing the roll-up door, and observers on the ground report that there's an unusual number of vehicles on site. SpaceX is probably working to secure the Cocoa construction yard as best as possible in advance of the storm.

SpaceX better tie down the Starship prototypes, or hurry them into the new hanger.

The tall "megachurch" hangar is almost complete. From the most recent photos, they are installing the roll-up door, and observers on the ground report that there's an unusual number of vehicles on site. SpaceX is probably working to secure the Cocoa construction yard as best as possible in advance of the storm.

It's good to keep in mind-again- that with any forecast for landfall we take the cone of uncertainty into account this far ahead in time. It's too early for any certainty of where it will hit Florida (or elsewhere on the U.S. mainland)

In related news, he and his crew pulled out over one hundred million dollars from FEMA to fund his border ...things. Any underesourced response from the Feds is directly, 100%, on him.

Really don't want to see anyone get hurt...but it would be rather interesting to see the response (from people and administration) if a major storm hits and the relief response falls on its face unable to do anything for lack of funding.

Trump needs to win Florida in order to stay president, plus his gawd-awful pimp palace is there. There will be plenty of funding for Florida. Puerto Rico on the other hand, is apparently not part of the US, and if it were it wouldn't vote for Trump, so they will get nothing except cases of generic paper towels and bottled water left somewhere inaccessible to the general public...

But didn't Trump once say that the president of Puerto Rico was doing a fine job, or was that the president of Guam?

That's right! He met with the President of the Virgin Islands! I knew something wasn't right about Puerto Rico or Guam, and I was beginning to think that he met with the President of Hawaii or the Prime Minister of Alaska. But you're right: he met with the President of the Virgin Islands. Thanks.

Yes, and Tropical Tidbits is a really nice source as well. During major storms such as Dorian, there are reaily informative daily video updates from Levi Cowan, who is a graduate student at FSU and is an excellent speaker. His site also includes live data from aircraft recon missions into the storms.

Regular people live there in that area.The damage they'd incur is apropos of what, exactly?

This entire thread is very telling of where people are at on the political spectrum and how they view those who don't share their political alignment. Honestly pretty chilling.

Happens all the time lately. People who never voted for (fill in 'wrong side' here) get lumped into the vengeance syndrome. Sucks to be them.

Edit "Oh, they're in a Red State so they deserve to be hurt by a natural disaster." Even if they never voted the 'wrong' way, and voting the 'wrong' way has never ever created a hurricane, they have it coming. Or something.Edit 2- If and when this storm (or any other) hits the U.S. mainland, these types of comment will be shared by mutton heads in bulk.

No worries. The VAB isn't going anywhere. And I think all the launch facilities are designed for this crap. Though repairs to the modified launcher for SLS will probably "need" another billion or so dollars after the storm.